The author speaks

Ark Royal's initial weaponry consists solely of an anti-meteor laser, a standard fitting for all fusion-powered ships which has been upgraded into the terawatt range and which possesses specific targeting software. Unusually for a ship its size, it also has a landing boat of its own, Sharman: a Boeing-Tupolev-Honda 177 Earth-orbit reusable entry vehicle.

In the novel, we are told:

His Majesty's Starship Ark Royal was a long, sleek ferro-polymer spindle three hundred feet long, its lines broken by the engine block at one end and the bulge of the centrifuge ring a third of the way down. At the far front of the ship was the anti-debris laser turret — the only armament that Ark Royal possessed. Aft of the laser was the forward airlock and then a stretch of hull, studded with the sockets that had held cargo containers in the ship's previous life as a freighter, that swept back to the wide disc of the ring compartment, ribbed by heat-dispersal fins. To Gilmore on the approaching Sharman, with the remaining two thirds of the hull hidden by the centrifuge, Ark Royal looked like a giant metal mushroom. The centrifuge ring held the crew quarters, the wardroom, the gym ...

The landing boat began to brake and slowly moved along the ship, and the remaining two thirds came into view. First came the boathouse — Sharman would fit snugly into its recess in the hull behind the ring, with only the wings of the arrowhead-shaped vessel protruding out into space. The boat, its reserve fuel tanks and Ark Royal's engineering section accounted for all of the space between the ring and the engine block.

Finally came the engines themselves — a triangle of liquid oxygen rockets around the central core of the fusion pulse engine.

That is the ship that Michael Gilmore takes over. It is not quite the ship that arrives at the Roving ...